Gaseous electric discharge device



June 7, 1932. M. PlRANl ET AL 1,861,581

GASEOUS ELECTRIC DISCHARGE DEVICE Filed July 24. 1950 INVENTORS ATTORNEY Patented June 7-, 1932 UNITED STATES PATENT OFFICE.

MARCELLO PIRANI, OI BERLIN-WTLKERSDORI', KARL BECKER, OI BERHN-STEGLITZ,

AND MARTIN BEGEB,

GASEOUB ELECTRIC Application filed July 24, 1980, Serial No.

The present invention relates to gaseous electric discharge devices generally and more particularly the invention relates to starting means for such devices.

It is well known in the art that in order to start such gaseous electric discharge devices into operation it is necessary to iomze the gas in the discharge path between the electrodes. It is equally well known that a high frequency current is useful for this purpose, said current being generated, in an auxiliary apparatus having a suitable circuit. It is a practice in the art to connect a choke coil into one of the leads of the electric discharge device 1 operating on alternating current, the function of said choke coil being to prevent the high frequency oscillations generated in the auxiliary apparatus during the starting period from entering the feeding circuit of the gaseous electric dischar e device.

ther function of said cho e coil is to serve as a resistance in the circuit of'the electric discharge device, said device bein operated on alternating current. In spite o the use of the choke coil in such a manner, certainty in I -starting the device was not always obtained. The reason for this uncertaint in the starting operation is that the capaclty of the normally wound choke coil used hitherto was too high and for that reason did .not offer sufficient resistance to prevent the passage of the high frequency current over the circuit back to the source thus dissipating its energy over the circuit instead of concentrating it on the electric discharge device.

The object of this invention is to insure certainty of starting electric discharge devices operating on sources of alternating current or direct current of the usual high and low volta es of commerce. The invention attains its 0 jects by means of a higli frequency apparatus used in conjunction with an open wound coil of low distributed capacity, both of these devices being cut into and out of circuit simultaneously by means of a suitgigble switching apparatus hereinafter described.

The open woundcoil oflow distributed capacity of the present invention is much less-expensive than the. choke coils used 4 OF BERLIN, GEBIANYQABBIGNQBS '1'0 GENERAL ELECTRIC COMPANY, A CORPORATION 01 NEW YORK mscmacm mwrcn 470,847, and in Germany August 38, 1029.

hitherto.- The coil of the presentinvention not only has a low distributed ca acity but is also considerably under dimensioned with respect to the intensity of the. operating current, Said coil'is connected into the circuit onl during the starting period while the high frequency apparatus is functioning; and it is instantly cut out of the circuit, together 'with the high frequency generator, by'means of a doubleacting switch on the starting of the electric discharge device when the roper operating current is going over the eeding circuit. Thus any inJury to the coil by the operating current is avoided and further even though the coil may be strongly heated by the high frequency starting cur- L rent this is not harmful as the passage of the high frequency starting current isbut momentary.

In the drawing accompanying and forming part of this specificatlon an embodiment of the new and novel starting apparatus is shown schematically.

Referring to the drawing the electric discharge device shown comprises a container 1. havlng electrodes 2, '3 sealed there1n,'said electrodes being connected to the terminals 6, 7 of an alternating current source by leads 4, 5 respectively. Lead 4 is provided with a double acting switch comprising a-conducting resilient member 9, which is provided .with a push button 11 and a contact 10 at one end thereof. Contact 8 of lead 4 makes contact 10 at one end thereof. Contact 8 of lead 4 makes contact with said resilient member 9. Pressure exerted manually, electrically, or mechanically on push-button 11 of resilient member 9 brings contact 10 into a contact making position with another contact 12 which is connected by leads 13, 13 to lead 4, said lejads 13, 13 beingconnected to a high frequency ap aratus conventionally shown at 14 and which, as is well known in the art, in the caseof analternating current.

source consists of a spark gap, an inductance,- an oscillatory circuit, and high frequency transformer and which in the case of a direct current'source consists of a magnetically operated circuit breaker and an inductance coil. The high frequency apparatus 14 is connected to lead 5 by leads 15, 15. A resistance 16 connected into said lead 5 serves as a ballast resistance when the elec- .tric discharge device 1 operates on normal low frequency or voltage. An open wound coil 18 of low distributed capacity considerably under dimensioned wit respect to the intensity of the low frequency operating current is connected into lead 4 by leads 17, 17

across the terminals of switch members 9, 8 a

stant by means of pressure exerted on button 11, this energizes the high frequency apparatus which starts the lamp. During this operation the contact between contact 8 and spring 9 is broken and the open wound coil 18 of low distributed capacity is put in the circuit. Said vcoil 18 has. such high resistance to high frequenc currents that during the high frequency ischarge none of the high frequency current passes it to reach the current source. Thus the high frequency current is'directed only to the electric discharge device which is thus started with certainty. After said device has been startedresilient member 9 is released to again make contact with contact 8 in which position the 'high frequency generator 14 and the open wound coil 18 are both out out of the circuit.

While we have shown anddescribedour device in conjunction with a gaseous electric discharge device of the positive column ty e it will be understood that we contemplate t e use of our invention in electric discharge devices generally which present problems in starting such as, for example, tungsten arc 43 lamps. And further it Wlll be understood that various substitutions, modifications and necting simultaneously said generator and said first mentioned means to and from said main source.

2. In combination, an electric discharge device, a high frequenc generator, a blockin impedance for high requency currents, an means for cutting into and out of circuit simultaneously the high frequency generator and the blocking impedance, said generator being adapted to start said electric discharge device and said blocking impedance being adapted to prevent the passage of the high frequency current to the current source of said electric discharge device.

-3. In combination, a gaseous electric discharge device, a high frequency generator, an open wound coilof low distributed capacity, and means for cutting into'and out of circuit simultaneously the high frequency generator and the open wound coil of low distributed capacity, said generator being adapted to start said gaseous electric discharge device and said open wound coil bein adapted to prevent the passage of the-hig frequency current to the current 'source of said gaseous electric discharge device.

In witness whereof we have hereunto set our hands this 9th day of July, 1930.

MARCELLO PIRANI KARL BECKER.

MARTIN REGER.

changes mayv bemade in details of the a I aratus shown without departing from t e road spirit and scope of the invention, for example, many other switching devices affecting the same result ma be substituted for resilient member 9.

What we claim as new and desire'to secure by Letters Patent of the UnitedStates, is:

1. In combination, an electric discharge device comprising a container, electrodes sealed thereln, a main source of current connected to said electrodes, and a'starting circuit for said device comprising 9. hi h frequency generator connected across t e terminals of said main-source and in operative relation to the terminals of said device, means in said circuit during starting for preventing oscillations therein passing to thesaid main source and means for connecting and discon- Ill 

